An American Bomb Left Over From World War II Explodes at an Airport Taxiway in Japan

Eight decades after World War II, an American bomb left over from the conflict exploded at a regional airport in Japan. Though the blast left a large hole in a taxiway and led to the cancellation of dozens of flights, no one was injured during the incident.

The 550-pound ordnance had been buried underground at Miyazaki Airport, located along the southwest coast of Japan. It detonated unexpectedly on the morning of October 2.

Investigations are still ongoing, but police and military officials say they don’t think the public is at risk of any additional danger.

“There is no threat of a second explosion, and police and firefighters are currently examining the scene,” says Yoshimasa Hayashi, chief cabinet secretary, as reported by BBC News’ Maia Davis.

Watch: U.S. Bomb From World War II Explodes at Japanese Airport | WSJ News

No aircraft were nearby at the time of the explosion, but the airport canceled more than 80 flights. According to Agence France-Presse, it resumed normal operations the next day.

A camera at a nearby aviation school captured footage of the blast, per the Associated Press’ Mari Yamaguchi. Moments after a plane taxied across the area, a fountain of asphalt and dust spewed into the air.

The explosion was over in just a few seconds, but the bomb left behind a crater that was reportedly three feet deep and seven yards in diameter, according to Japanese television broadcasts.

In response to the explosion, Japanese officials ordered a sweep of Miyazaki and other regional airports for additional bombs, reports the South China Morning Post’s Julian Ryall.

American troops likely dropped the bomb in a bid to stop kamikaze attack missions departing from the airport. The facility was built in 1943 as an Imperial Japanese Navy base.

Japanese officials are looking into what caused the bomb to go off after so many years. One possibility is that the explosion was triggered by vibrations from the airplane driving above it on the surface, per the South China Morning Post.

“These bombs are usually safe, although if they are disturbed or their inner workings get wet then they can become more unstable,” Garren Mulloy, a scholar of international relations at Japan’s Daito Bunka University, tells the publication. “Over time, the detonator and primer can deteriorate, but also many were fitted with trembler switches that would detonate the device if someone tries to defuse them after they have been dropped. The bottom line is that they are less predictable if they did not go off as they were originally designed to do.”

Unexploded American ordnances from World War II are still buried all over Japan, though they rarely detonate. Last year, Japan disposed of 2,348 bombs weighing 41 tons, per Reuters’ Kantaro Komiya. The bombs are sometimes unearthed during construction projects and safely disarmed by specialists.

Unexploded World War II bombs also remain hidden in Europe and other parts of Asia. In October 2023, a Japanese bomb was discovered at a suburban construction site in Singapore.

Several such bombs have been uncovered in 2024. In February, a woman found a German bomb in her backyard in Plymouth, England, leading to the evacuation of 10,000 people. A few months later, a construction crew working in Cologne, Germany, discovered an unexploded bomb in the Rhine River. An unexploded American bomb was unearthed in Mainz, Germany, around the same time.